the massive hunt for the most-wanted woman in the world right now. You see her here. She is called the white widow. Authorities say she's tied to terrorism and may be linked to the kenya mall massacre. Now, an international arrest warrant is out for her. And brian ross is here with the very latest. Good morning, brian. Reporter: Good morning, josh. British police will be seeking dna samples from the family of the so-called white widow, samantha lewthwaite, according to officials. The point is to see if the dna matches with any of the female bodies discovered in the rebel in the westgate mall in kenya. Overnight, a global arrest warrant for the 29-year-old lewthwaite, now one of the most wanted women in the world. Samantha lewthwaite has been a wanted person for a number of years now. Reporter: Authorities in kenya have no hard evidence of her involvement of what happened here. But they're seeking to see if she was involved in the brutal attack. Based on her known ties to african terror groups and eyewitness accounts that a mystery woman was part of the attack. It was a woman throwing a grenade at us. Reporter: Counterterrorisms say lewthwaite has been involved with the al shabaab group that claimed responsibility for the massacre. She wants to die or martyr herself on behalf of that group. Reporter: Lewthwaite grew up in a small town north of london. Over 15 years time, went from schoolgirl to party girl. To wife 06 one of the terrorists, who carried out suicide attacks on the london subway and bus system in 2004. After the attacks, lewthwaite, a mother of two, denied knowledge of her husband's al qaeda ties. And family friends said she was a decent girl. Very innocent. Lacking confidence. Shy. Easy to get on with. Reporter: Since then, authorities say lewthwaite slipped out of england with her children, and joined up with the african terrorists. Flying to kenya under the name of natalie faye web. She has been wanted for another attack on a nightclub in kenya. And interpol expresses an urgency to find her. You'll be on top of that, brian. Now, to washington, where a

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